Find all angles, o<Θ<360, that satisfy the equation below, to the nearest 10th of a degree. 4cos^2Θ-2=-1

30° and 150°

Step-by-step explanation:

We want to find the angles in the range:

0° < θ < 360°

Such that:

4*cos^2(θ) - 2 = 1

The first part is to isolate the variable θ in one side of the equation, let's do that:

4*cos^2(θ) = 1 + 2 = 3

cos^2(θ) = 3/4

cos(θ) = ± √(3/4) = ± (√3)/2

Then we have two possible values of θ, one for:

cos(θ) =  (√3)/2

And another for

cos(θ) = - (√3)/2

For both cases, we can use the inverse cosine function, Acos(x)

that has the property Acos( cos(x) ) = x

Then:

cos(θ) =  (√3)/2

Acos( cos(θ) ) = Acos(  (√3)/2)

θ = Acos(  (√3)/2) = 30°

And for the other case we have:

θ = Acos( - (√3)/2) = 150°

Then the two values of theta are: 30° and 150°

(We can see that both of these values are in the range 0° < θ < 360°)

distance covered by pamela in 9 l of fuel = 99km

let us apply unitary method here.

distance covered by pamela in 1 l of fuel =99/9 =11 km

now let us find distance covered by pamela if she has 12 l of fuel.

distance covered in 12 l = distance covered in 1 l of fuel * 12

we know that distance covered by here in 1 l is 11 km.

so distance covered in 12 l of fuel = 11*12 = 132 km.

good luck on your studies! : )

david edward.